How it works
When Claude produces a supported file type (such as a .png, .jpg, or .svg), it will attach a content credential in the form of a small, cryptographically signed note in the file’s metadata, saying that the file was made or processed with Claude.
This is an open industry standard called C2PA—the same used by camera manufacturers and in photo-editing software to record where an image came from. Any C2PA-aware tool can read it
If we find one that points to Claude, we'll tell you here.
Similar tools are available from other model providers (OpenAI, Google DeepMind, Gemini).
How can I tell if Claude created the text?
To detect watermarks embedded in text we have a Detection API which is currently in private preview to eligible organizations as required under EU law.
Read more about file and text detection here.